Electrical Machines What is/are the advantages of parallel operation of alternators? Increase efficiency under light load conditions continuity supply is maintained Increase in reliability All of these Increase efficiency under light load conditions continuity supply is maintained Increase in reliability All of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines How can the synchronous speed of a 3 - Φ IM be varied? Both (A) and (B). By varying the supply frequency. By varying number of poles. By varying supply voltage. Both (A) and (B). By varying the supply frequency. By varying number of poles. By varying supply voltage. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The brush-axis of a bipolar dc motor is rotated by 90°. The effect of this rotation on the back emf Eband the torque developed Tdwould be such that both Eb and Td are zero Eb is zero, but Td is unchanged both Eb and Td are unchanged Eb is unchanged, but Td is zero both Eb and Td are zero Eb is zero, but Td is unchanged both Eb and Td are unchanged Eb is unchanged, but Td is zero ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines In a 3 - Φ wound rotor induction motor the short circuit gear is used to short circuit the starting resistance in the starter. stator phases of the motor. rotor at slip rings. None of these starting resistance in the starter. stator phases of the motor. rotor at slip rings. None of these ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines Voltage across the open circuited field termninals of a synchorous machine under slip test is A modulated supply frequency AC voltage with slip frequency envelop. DC of slip frequency. AC of supply frequency. DC. A modulated supply frequency AC voltage with slip frequency envelop. DC of slip frequency. AC of supply frequency. DC. ANSWER DOWNLOAD EXAMIANS APP
Electrical Machines The starting resistance of DC motor is generally Low. around 500 ohms. 1000 ohms. Infinitely large. Low. around 500 ohms. 1000 ohms. Infinitely large. ANSWER DOWNLOAD EXAMIANS APP